Cube.rock: converted to binary fixed-point arithmetic allowing for some more optimisation, and added proper aspect handling of LCDs with non-square pixels (all archos SH targets).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7126 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 66 insertions, 62 deletions

diff --git a/apps/plugins/cube.c b/apps/plugins/cube.c
index bce4ffcd97..f4e0e01c41 100644
--- a/apps/plugins/cube.c
+++ b/apps/plugins/cube.c
@@ -9,6 +9,7 @@
 *
 * Copyright (C) 2002 Damien Teney
 * modified to use int instead of float math by Andreas Zwirtes
+* binary fixed point format and LCD aspect handling by Jens Arnold
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
@@ -90,47 +91,45 @@ static int nb_points = 8;
 #define DIST (10*LCD_HEIGHT/16)
 static int x_off = LCD_WIDTH/2;
 static int y_off = LCD_HEIGHT/2;
+#if CONFIG_LCD == LCD_SSD1815
+#define ASPECT 320 /* = 1.25 (fixed point 24.8) */
 #else
+#define ASPECT 256 /* = 1.00 */
+#endif
+#else /* !LCD_BITMAP */
 #define MYLCD(fn) pgfx_ ## fn
 #define DIST 9
 static int x_off = 10;
 static int y_off = 7;
-#endif
+#define ASPECT 300 /* = 1.175 */
+#endif /* !LCD_BITMAP */
 
-static int z_off = 600;
 
-/* Precalculated sine and cosine * 10000 (four digit fixed point math) */
-static int sin_table[91] = 
+static long z_off = 600;
+
+/* Precalculated sine and cosine * 16384 (fixed point 18.14) */
+static short sin_table[91] =
 {
-    0, 174, 348, 523, 697,
-    871,1045,1218,1391,1564,
-    1736,1908,2079,2249,2419,
-    2588,2756,2923,3090,3255,
-    3420,3583,3746,3907,4067,
-    4226,4383,4539,4694,4848,
-    5000,5150,5299,5446,5591,
-    5735,5877,6018,6156,6293,
-    6427,6560,6691,6819,6946,
-    7071,7193,7313,7431,7547,
-    7660,7771,7880,7986,8090,
-    8191,8290,8386,8480,8571,
-    8660,8746,8829,8910,8987,
-    9063,9135,9205,9271,9335,
-    9396,9455,9510,9563,9612,
-    9659,9702,9743,9781,9816,
-    9848,9876,9902,9925,9945,
-    9961,9975,9986,9993,9998,
-    10000
-};  
+        0,   285,   571,   857,  1142,  1427,  1712,  1996,  2280,  2563,
+     2845,  3126,  3406,  3685,  3963,  4240,  4516,  4790,  5062,  5334,
+     5603,  5871,  6137,  6401,  6663,  6924,  7182,  7438,  7691,  7943,
+     8191,  8438,  8682,  8923,  9161,  9397,  9630,  9860, 10086, 10310,
+    10531, 10748, 10963, 11173, 11381, 11585, 11785, 11982, 12175, 12365,
+    12550, 12732, 12910, 13084, 13254, 13420, 13582, 13740, 13894, 14043,
+    14188, 14329, 14466, 14598, 14725, 14848, 14967, 15081, 15190, 15295,
+    15395, 15491, 15582, 15668, 15749, 15825, 15897, 15964, 16025, 16082,
+    16135, 16182, 16224, 16261, 16294, 16321, 16344, 16361, 16374, 16381,
+    16384
+};
 
 static struct plugin_api* rb;
 
 static long sin(int val)
 {
     /* Speed improvement through sukzessive lookup */
-    if (val<181)
+    if (val < 181)
     {
-        if (val<91)
+        if (val < 91)
         {
             /* phase 0-90 degree */
             return (long)sin_table[val];
@@ -143,15 +142,15 @@ static long sin(int val)
     }
     else
     {
-        if (val<271)
+        if (val < 271)
         {
             /* phase 181-270 degree */
-            return (-1L)*(long)sin_table[val-180];
+            return -(long)sin_table[val-180];
         }
         else
         {
             /* phase 270-359 degree */
-            return (-1L)*(long)sin_table[360-val];
+            return -(long)sin_table[360-val];
         }
     }
     return 0;
@@ -160,9 +159,9 @@ static long sin(int val)
 static long cos(int val)
 {
     /* Speed improvement through sukzessive lookup */
-    if (val<181)
+    if (val < 181)
     {
-        if (val<91)
+        if (val < 91)
         {
             /* phase 0-90 degree */
             return (long)sin_table[90-val];
@@ -170,15 +169,15 @@ static long cos(int val)
         else
         {
             /* phase 91-180 degree */
-            return (-1L)*(long)sin_table[val-90];
+            return -(long)sin_table[val-90];
         }
     }
     else
     {
-        if (val<271)
+        if (val < 271)
         {
             /* phase 181-270 degree */
-            return (-1L)*(long)sin_table[270-val];
+            return -(long)sin_table[270-val];
         }
         else
         {
@@ -193,40 +192,40 @@ static long cos(int val)
 static void cube_rotate(int xa, int ya, int za)
 {
     int i;
-
     /* Just to prevent unnecessary lookups */
-    long sxa,cxa,sya,cya,sza,cza;
-    sxa=sin(xa);
-    cxa=cos(xa);
-    sya=sin(ya);
-    cya=cos(ya);
-    sza=sin(za);
-    cza=cos(za);
+    long sxa, cxa, sya, cya, sza, cza;
+
+    sxa = sin(xa);
+    cxa = cos(xa);
+    sya = sin(ya);
+    cya = cos(ya);
+    sza = sin(za);
+    cza = cos(za);
 
     /* calculate overall translation matrix */
-    matrice[0][0] = cza*cya/10000L;
-    matrice[1][0] = sza*cya/10000L;
+    matrice[0][0] = (cza * cya) >> 14;
+    matrice[1][0] = (sza * cya) >> 14;
     matrice[2][0] = -sya;
 
-    matrice[0][1] = cza*sya/10000L*sxa/10000L - sza*cxa/10000L;
-    matrice[1][1] = sza*sya/10000L*sxa/10000L + cxa*cza/10000L;
-    matrice[2][1] = sxa*cya/10000L;
+    matrice[0][1] = (((cza * sya) >> 14) * sxa - sza * cxa) >> 14;
+    matrice[1][1] = (((sza * sya) >> 14) * sxa + cxa * cza) >> 14;
+    matrice[2][1] = (sxa * cya) >> 14;
 
-    matrice[0][2] = cza*sya/10000L*cxa/10000L + sza*sxa/10000L;
-    matrice[1][2] = sza*sya/10000L*cxa/10000L - cza*sxa/10000L;
-    matrice[2][2] = cxa*cya/10000L;
+    matrice[0][2] = (((cza * sya) >> 14) * cxa + sza * sxa) >> 14;
+    matrice[1][2] = (((sza * sya) >> 14) * cxa - cza * sxa) >> 14;
+    matrice[2][2] = (cxa * cya) >> 14;
 
     /* apply translation matrix to all points */
-    for(i=0;i<nb_points;i++)
+    for (i = 0; i < nb_points; i++)
     {
-        point3D[i].x = matrice[0][0]*sommet[i].x + matrice[1][0]*sommet[i].y
-            + matrice[2][0]*sommet[i].z;
+        point3D[i].x = matrice[0][0] * sommet[i].x + matrice[1][0] * sommet[i].y
+                     + matrice[2][0] * sommet[i].z;
         
-        point3D[i].y = matrice[0][1]*sommet[i].x + matrice[1][1]*sommet[i].y
-            + matrice[2][1]*sommet[i].z;
+        point3D[i].y = matrice[0][1] * sommet[i].x + matrice[1][1] * sommet[i].y
+                     + matrice[2][1] * sommet[i].z;
         
-        point3D[i].z = matrice[0][2]*sommet[i].x + matrice[1][2]*sommet[i].y
-            + matrice[2][2]*sommet[i].z;
+        point3D[i].z = matrice[0][2] * sommet[i].x + matrice[1][2] * sommet[i].y
+                     + matrice[2][2] * sommet[i].z;
     }
 }
 
@@ -235,12 +234,17 @@ static void cube_viewport(void)
     int i;
 
     /* Do viewport transformation for all points */
-    for(i=0;i<nb_points;i++)
+    for (i = 0; i < nb_points; i++)
     {
-        point2D[i].x=(((point3D[i].x)<<8)/10000L)/
-          (point3D[i].z/10000L+z_off)+x_off;
-        point2D[i].y=(((point3D[i].y)<<8)/10000L)/
-          (point3D[i].z/10000L+z_off)+y_off;
+#if ASPECT != 256
+        point2D[i].x = (point3D[i].x * ASPECT) / (point3D[i].z + (z_off << 14))
+                     + x_off;
+#else
+        point2D[i].x = (point3D[i].x << 8) / (point3D[i].z + (z_off << 14))
+                     + x_off;
+#endif
+        point2D[i].y = (point3D[i].y << 8) / (point3D[i].z + (z_off << 14))
+                     + y_off;
     }
 }